Among various inorganic membranes, hollow fiber carbon membranes have excellent gas separation properties, and can be used in an environment that requires such high heat resistance and chemical resistance that organic membranes cannot be applied; thus, the practicability of hollow fiber carbon membranes has been highly anticipated. Further, due to the excellent pressure resistance and large membrane area per unit volume, hollow fiber carbon membranes enable the production of compact separation membrane modules.
As carbon membranes having these characteristics, Patent Document 1 discloses a method for producing a hollow fiber carbon membrane comprising a polyimide, and Patent Document 2 discloses a method for producing a hollow fiber carbon membrane comprising a polyphenylene oxide derivative.
A further improvement in processing performance has been required in recent years, and it is challenging to improve the permeability of hollow fiber carbon membranes without reducing their separation coefficient.